DIET OF COMMON RAVENS ON EL HIERRO, CANARY-ISLANDS

The Common Raven (Corvus corax) on El Hierro, an oceanic island in the Canary archipelago, is omnivorous. Although ravens from five regions on El Hierro showed qualitatively similar diets, there were considerab le quantitative differences. Diet in wet and dry pastureland was made up principally of animals: invertebrates at Jinama (frequency of occur rence in pellets = 84.8%) and high levels of vertebrates at Bascos (60 %). Spring was characterized by the consumption of vertebrates (freque ncy in pellets = 48.5%), summer by invertebrates (77.1%), and autumn/w inter by a diet of plant material (92.6% and 96.9%, respectively). Whi le diets in many continental environments are often characterized by v ertebrates throughout the year, ravens on El Hierro tend to be omnivor ous, including many insects and wild fruits in their food.